Jijii is the homeroom teacher of class 1D. He always has an armband on his left arm that has different text every time its shown the text being anything from the title of the episode to an adage. He is surprisingly lively for his old age and is seen as strange by his students but the feeling is actually mutual. quotJijiiquot quotJijiiquot? is used to address a grandfather or an old man in Japanese. He is known for using different quotscare tacticsquot in order to keep his class in order the first of which was his promise to stand by his students beds if they were to skip class. wikipedia